Thursday brought the broadest market selloff of 2026 so far, but copper apparently didn't get the memo. The orange metal rallied to an all-time high, touching $14,268 per metric ton on the London Metal Exchange. Good news for miners, right? Well, not exactly.

The blistering rally may actually complicate what could become the mining industry's biggest-ever deal: a proposed $200 billion merger between Rio Tinto Plc (RIO) and Glencore Plc (GLCNF).

Why Copper Is Exploding

A weaker U.S. dollar helped amplify gains across all metals, since most commodities trade in dollars. But the real story is copper's starring role in the technology transition. Electrification, AI infrastructure, defense spending, and data center expansion are all incredibly copper-intensive.

Here's the thing: copper's surge is no longer a simple proxy for near-term economic health. The metal has long been nicknamed "Dr. Copper" for its supposed ability to diagnose the global economic cycle, but it's decoupled from that old paradigm. The rally is less about immediate demand and more about forward-looking scarcity. Prolonged underinvestment, declining ore grades, and regulatory constraints have made new mine supply harder to find and harder to deliver.

The Production Problem

That structural scarcity narrative sits awkwardly with Glencore's actual production performance. The miner reported that its copper output fell 11% in 2025 to 851,600 tons, hitting the low end of guidance as weaker ore grades and operational constraints hammered volumes.

Production rebounded somewhat in the final quarter, but the underlying problem persists. For 2026, Glencore expects output between 810,000 and 870,000 tons, owing to issues at the Collahuasi mine in Chile. The midpoint of that range sits well below a previous forecast of 930,000 tons.

This reality complicates the potential mega-merger. Investors view copper as the core rationale for any tie-up between Rio Tinto and Glencore, yet soaring prices don't automatically translate into near-term production growth. Copper is a prized asset right now, but it's not easily expandable.

Volatility Eating Itself

Meanwhile, extreme prices are bringing extreme volatility along for the ride. Physical demand, particularly in China, has already shown signs of strain at these elevated levels. Parts of the market are thinning as risk limits get hit and participants back away.

"When things go exponential, a lot of the banks start to withdraw due to their risk tolerance," Dan Smith, managing director at Commodity Market Analytics, told Reuters.

"The volatility just makes it brutal to try and trade it," he added, explaining that this dynamic creates narrower market participation. That has the potential to self-reinforce, since smaller volume increases volatility potential even further.

The Global X Copper Miners ETF (COPX) is up 31.26% year-to-date.

RIO Price Action: Rio Tinto shares were down 2.61% at $92.65 during premarket trading on Friday. The stock is approaching its 52-week high of $97.11.